In traditional hybrid/dual input systems that support both touch and pen input on a touch screen there are a number of problems that cause a poor user experience. One significant problem is accidental touch inputs by the user while she is writing with a stylus. Typically, a user will rest her hand or palm on the touch screen display during the act of writing with the stylus. The user's hand or palm contact with the screen can generate touch input that resembles finger inputs. This limitation of traditional systems has caused these systems to develop exclusive modes of input. For example, during a note taking applications input is limited to pen only in order to avoid erroneous touch detection described above.
In traditional systems, a user needed to manually change the input mode from pen to touch or from touch to pen.